Hi. There are several proven approaches you can test to see what is more effective to your specific public. I can elaborate them better after getting some further details about your marketing strategy.

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1. Turn subscribers into affiliates
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Just offer a discount or any other benefit which your subscribers would appreciate. Such tracking is easy to do with affiliate ready-made tools.

This strategy is very powerful. A good example is the Dropbox case: they grew 3900% in 15 months mainly by giving extra free space to their affiliates and referred users.

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2. Are you using lead magnets?
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Whichever is the medium you are reaching your potential subscribers, make sure to tease them properly, by giving a freebie (PDF, webinar or whatever) in exchange to their precious emails.

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3. How exactly is your free content?
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Either it is a lead magnet, blog article, video, each piece of free content you provide has 3 purposes:
1) To provide value to the prospect.
2) To establish your authority.
3) To drive prospects towards action.

Just think about the biggest immediate problem your ideal prospects might have, mapping out ONE thing they must do to solve it.

Remember to put your focus solely on that one thing, being as specific as possible. In the end, promote your paid subscription.

Then make several freebies like this covering different topics.

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4. Paid advertising
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I would recommend you to run ads targeting prospects with specific job titles and/or from specific industries etc, on LinkedIn and Facebook.

Yes, I said Facebook. I know top millionaire professionals reaching 7-figure serious clients with Facebook Ads with great success (best example I know: Frank Kern).

You can run lead-generation ads, using lead magnets as I've described above.

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5. What about YouTube?
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Besides the high search volume within YouTube, their hosted videos have a high relevance on Google searches (especially because they are own by Google).

The main difference in the YouTube strategy is that your prospect will start the interaction seeing your content rather than first giving their email to then see the content. A workaround is to talk about the subject mentioning they can download a PDF with the framework to solve the problem. So when they click on the link in your video description you're gonna collect their emails.

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6. How is your marketing automation?
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The vast majority of people who receive our marketing messages say no. That's just the human nature, no matter how skilled we are.

That's why we have to track non-converted prospects and bring them back with a smart approach.

Nowadays we have several ways of tracking prospects behaviour in order to divert them to specific funnels according to their interactions, such as: who opened or not the email, watched the webinar, watched only X% of it, downloaded or not a PDF etc.

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7. Get a qualified coach
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Just give me a call and I can coach you on any of above proven strategies, so that we can draw a marketing plan tailored to your own goals and niche.

Best regards,
Carlos.